Adwords vs. Referral Logs

[Trodda]

Busy trying out some new log analysis software. Found that my Google Adwords clicks are double as many as my logged referrals from Google. Any idea how this could be?

[rogerd]

Discrepancies are fairly common - how are you tracking the referrals, Trodda? If each click loads a unique URL, your data should be closer than if you rely on referrer data. Referrer data is unreliable for accounting purposes.

Some clicks may not go through to completion, too - i.e., the visitor may click on the ad but may do something else before the page request is properly logged on your system.

[Trodda]

Rogerd, we actually use a separate system to track all our campaigns (e.g.Adwords) whereby we assign a redirect ID for each keyphrase. We find this method to be very accurate. With the log analysis software I was hoping to get an idea of the number of referrals we were getting from a natural search point of view as well. Clearly this data is not going to help too much.

[rogerd]

Log analysis is far from precise, unfortunately. The reports give the appearance of great accuracy and detail, confidently assuring you that you had ___ visits from ___ unique visitors, ___ referrals from example.com, etc. In reality, shifting and multiple IP addresses, missing referrer & other data, etc. conspire to make these estimates.

Log analysis still definitely worth doing, though, as there's lots of good information even if it isn't up to "accounting" precision.